Exhauster ventilator



Oct. 7, 1958 H. KNUTSON EIAL 2,854,916

EXHAUSTER VENTILATOR Filed D60. 14, 1955 INVENTORS: R01- 0 Kw 1-.ro/v y HA Row G. flvursolv United States Patent O EXHAUSTER VENTILATOR Harold Knutson and Harold G. Knutson, Chicago, 111.

Application December 14, 1955, Serial No. 553,115

Claims. (Cl. 98-116) This invention relates in general to a roof ventilator for the vertical high velocity expulsion of offensive fumes, dust, steam, excessive heat and smoke by dissipation high in the air and is more particlularly described as an exhauster having dampers which automatically open and close against down draft, rain or snow.

An important object of the invention is to provide an exhauster ventilator of the rotating fan type which may be readily set up on proper curbings around roof openings.

A further object of the invention is to provide a high velocity exhauster ventilator for dissipating fumes and the like, high in the air, preventing roof damage and re-entry of such fumes when fresh air intakes are also located on the roof.

A further object of the invention is to provide dampers ordinarily opened and closed by the air pressure of the fan for effectively sealing the discharge stack against down draft, rain or snow when the fan is not in operation.

Still a further object of the invention is to provide automatic means for opening the dampers in case of fire and to relieve the ventilated area in a highly heated condition.

A still further object of the invention is to provide an efiective and efficient roof ventilator which is strongly constructed of sheet metal and erected in circular form so that it is not easily damaged and is therefore subject to long wear and continued use.

Other objects of the invention will appear in the specification and will be apparent from the accompanying drawings in which,

Fig. 1 is a perspective view of an exhauster ventilator in accordance with this invention with parts of the outer walls broken away to show the inner construction and operations more clearly.

Fig. 2 is a sectional view of rotatable dampers and operating levers retained by fusible links in closed position;

Fig. 3 is a part sectional view showing the dampers in open position as raised by the lever arms when the fusible links are broken;

Fig. 4 is a perspective view of one end of the discharge gutter; and

Fig. 5 is a fragmentary perspective view showing the plate closing levers and springs.

In this ventilator, the rotation of the exhauster fan opens butterfly valves which are also automatically opened in case of a highly heated condition in the ventilator stack.

Referring now more particularly to the drawings, this ventilator is mounted upon a supporting casing of sheet metal having an upper circular mounting ring 12 and a bottom rectangular flange .14 adapted to be seated over a roof curb surrounding a correspondingly shaped ventilator opening or secured to any other suitable support.

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Supported by the mounting ring 12 is a circular fan barrel 16 of sheet metal extending upwardly and carrying an upwardly extending storm band 18 also preferably made of sheet metal and larger in diameter than the fan barrel 16 so that these parts are secured together in spaced relation by brackets 20 at intervals around these bands so that they are concentric and evenly spaced from each other about their peripheries with the upper edge of the storm band extending a considerable distance above the upper edge of the fan barrel.

Extending across the fan barrel is a supporting plate 22 preferably somewhat eccentric to the fan barrel so that an electric motor 24 may be mounted upon this plate with its axis centrally of the fan barrel. A fan 26 is secured to the upper end of the shaft of the electric motor 24 and the blades fit closely within but are freely rotatable within the fan barrel adjacent the top thereof.

Extending across the top of the fan barrel is a support 28 having parallel sides 30 with a V-shaped gutter 32 depending between them, which discharges water or other materials from the gutter into the space between the fan barrel and the storm band free from contact with the motor and free from the inside of the ventilator. The support and gutter are preferably seated within the opposite edges of the fan barrel.

Hinged to the sides 30 of the support 28 are semicircular plates 34 which form butterfly valves for together closing the upper end of the fan barrel over the top of the fan 26. A supporting cross piece 36 of metal which may be in the form of a channel extends across the upper end of the storm band and is secured thereto in any desired manner. This cross piece is parallel with the support 28 for the valve plates 34 and engages these plates to limit their upward movement so that they will fall freely when not thrust upwardly by the fan 26. At the inside of each valve plate 34 is a plate 38 with flanged edges for securing it in offset inclined position to the under side of the valve plate 34 for projecting the motor and fan from dripping condensation of moisture which may collect at the under side of the plate 34, and discharging it from the outer edge of the plate 38 outwardly in the fan barrel beyond the motor. This plate may also act as a weight to move the valve plate 34 to which it is attached in a downward direction from its uppermost position.

Also hinged at the sides of the support 28 to which the valve plates 34 are hinged are two levers 40, at least one at each side of the support 28 mounted upon a pivot 42 carried by the support and each lever having two arms extending from the pivot at an angle to each other, one arm 44 extending below one of the valve plates 34 in its downward position and the other arm 46 of each lever extending relatively below the pivot 42 of the opposite lever so that a fusible link 43 may be connected between the pivot of each lever and the end of the arm 46 of the other lever.

Each arm 46 is connected by a coil spring 50 attached at one end to the arm and extending below the gutter 32 of the support to the opposite side of the fan barrel to which the other end is secured.

As shown in Fig. 2, the levers 40 are held below the valve plates 34 in their lowered position with the fusible links holding the levers 40 against the tension of their corresponding springs 50 for operating the levers and raising the plates to the position shown in Fig. 3 when the fusible links 48 are broken because of undue heat, or for any other reason as shown in Fig. 3.

With this construction, the valve plates 34 are opened automatically 'by the ventilator fan 26 whenever it is operated, the air current from the fan being sufiicient to raise the plates against the cross piece 36 but the inclination of the plates in their raised position being such that they will descend by their own weight to a position closing over the edge of the fan barrel 16, the edges of the valve plates preferably overlapping the top of the fan barrel so that the rain, snow and any other material which enters the outer storm band will be deflected from a downward movement in the fan barrel and will be discharged around the fan barrel in a space between it and the storm band. Thus the fan barrel is closed against down draft, rain, snow, dust and other dirt. If the ventilator stack becomes too hot due to a fire or internal heat within the building to which it is applied, the valve plates are automatically opened by the breaking of the fusible links which causes the levers 40 to be actuated by their springs 56 to engage the under sides of the valve plates 34 and to raise them to their upper position in contact with the cross piece 36. The valve plates will remain in this position until the levers 40 are manually withdrawn to their down position as shown in Fig. 2 against their respective springs and again secured by fusible links 48 or other suitable fastening means.

At one side of the fan barrel is an access panel 52 in the portion below the storm band so that access may be had to the fan motor 24, the fusible link 48 and the operating levers 4t) and other inner parts of the ventilator without necessity of entirely dismantling it.

With this construction, this exhauster ventilator is so constructed and operated that automatic and positive control is assured through the ventilator without back pressure or turbulence. The valve plates are jointly operated by the fan to open and close them during normal operation and by the spring pressed arms to additionally open them automatically in an emergency condition.

While a preferred embodiment of the invention has been described in some detail, it should be regarded as an illustration or example rather than as a limitation or restriction of the invention, since various changes in the construction, combination, and arrangement of the parts may be made without departing from the spirit and scope of the invention.

1 claim:

1. In a ventilator, an open circular fan barrel supported at the bottom, a motor fan mounted centrally in the fan barrel for causing a draft therethrough, a support secured to and extending across the top of the fan barrel, a pair of semi-circular valve plates hinged diametrically to the support and together covering the top of the fan barrel, the valve plates being raised by a draft induced by the fan to an outer open position, two levers pivoted intermediate their ends on opposite sides of the support, each having one arm freely engaging the under side of the adjacent valve plate in closed position, and another arm of each lever extending oppositely and downward below and adjacent the other side of the support, a fusible link for connecting the last named arm to the side of the support opposite the pivot of its lever, and spring means having one end connected to the last named arm of each lever and extending oppositely below the support and the other end of the spring connected to the opposite portion of the fan barrel, and operative to resiliently engage the under side of its respective plate to an open position when the fusible link is broken.

2. In a ventilator according to claim 1, the fusible link for each lever being connected at one end to the said arm and at the other end to the pivot of the lever at the opposite side of the support, and the spring means extending from the arm to which the fusible link is connected and across and below the support to the opposite side of the fan barrel, and operative to swing the corresponding lever and its valve plate to open position when its fusible link is broken.

3. In a ventilator according to claim 1, the support being in the form of a central gutter secured in opposite diametric edges of the fan barrel and extending beyond the said edges thereof, the levers being mounted upon opposite sides of the support with one arm of each lever extending below the gutter, the ends of the gutter forming discharges beyond the opposite sides of the barrel, and a storm band secured, to spaced from and surrounding the fan barrel from a point below the gutter to a point above the upper end of the fan barrel, and a cross piece secured at the upper end of the storm band for engaging the plates and limiting their upward movement.

In a ventilator in accordance with claim 3, the valve plates having deflectors at their under sides overlying portions of the motor and the central portion of the fan and forming a.weight tending to swing the plate downwardly and the deflectors being spaced from the plates and located to incline downwardly and discharge moisture from the under side of the valve plate and outwardly in the fan barrel beyond the motor, and the central portion of the fan to protect the motor and fan in their position at the top of the shell when the plates are closed.

5. In a ventilator in accordance with claim 4, the valve plates being hinged diametrically on said support and normally inclined downwardly at the outer edge adjacent th fan barrel in their closed position, and the deflectors also inclined downwardly-and outwardly from the central support for discharging condensation from between the deflectors and the' iinder sides of the plates from the outer edge of the deflectors into the space outwardly in the fan barrel beyond the motor and the inner portion of the fan blades.

References Cited in the file of this patent UNITED STATES PATENTS 

